Longitudinal web folding board



Sept. 17, 1968 R. H. FRICK ET LONGITUDINAL WEB FOLDING BOARD 6 Sheets-Sheet 1 Filed July 25, 1966 Sept 17, 1968 R, H. FRICK ET AL 3,401,927

LONGITUDINAL WEB FOLDING BOARD Filed July 25, 196 3 Sheets-Sheet 2 Sept. 17, 1968 R.H. FRICK ET AL 3,401,927

LONGITUDINAL WEB FOLDING BOARD Filed July 25, 1966 3 Sheets-Sheet 5 3,401,927 LONGITUDINAL WEB FOLDING BOARD Richard H. Frick and Herbert H. Scholz, Neenah, Wis., assignors to Kimberly-Clark Corporation, Neenah, Wis., a corporation of Delaware Filed July 25, 1966, Ser. No. 567,440 6 Claims. (Cl. 270-40) ABSTRACT OF THE DISCLOSURE A folding device for both overfolding and underfolding lateral strips of a web of sheet material with respect to a central zone of the web including first, second and third folding edges disposed in a single plane and joining at a single point, a fourth folding edge extending from said point at obtuse angles to said first and second folding edges so that the central zone of the web may be passed over the first folding edge while a lateral edge strip of the web passes successively over the fourth, second and third folding edges to be folded underneath the central zone of the web, said folding device also including a fifth folding edge extending from a second point on said first folding edge spaced from said first point and extending obliquely with respect to said first folding edge and being disposed in the same plane as said fourth folding edge and a sixth folding edge substantially in said first named plane and extending from said second point to said second folding edge so that a lateral edge strip of the web may successively pass over said fifth and sixth folding edges to be folded over said central zone of the web.

Our invention relates to papermaking machines and more particularly to machines for interfolding Webs of paper or other sheet material.

It has been previously proposed in US. Patent 3,066,- 932 issued Dec. 4, 1962, to Charles I. Greiner and Harold V. Rutkus, that folding boards be provided of such construction that they turn a lower fold underneath a top fold of a web passing over the board so as to thereby effectively fold the web along a longitudinal line of the web. The folding boards are each provided with a flat guide portion extending in the path of movement of previously folded webs over which a top fold of a previously folded web may pass so that the web being underfolded by the folding board is also folded under the top fold of the previously folded web so as to thereby interfold the webs.

It is desirable that the uppermost fold of a stack of longitudinally folded webs be partially folded across itself to provide a folded edge centrally located on the top of the stack so that a person reaching through a longitudinally extending central slot in the uppermost panel of a carton containing a clip or segment of a stack of such interfolded webs may easily grasp the uppermost fold, and it is an object of the present invention to provide an improved folding board of the type suggested in the Greiner and Rutkus Patent 3,066,932, which may be utilized for partially folding the uppermost fold of a stack of longitudinally interfolded webs partially over itself for this purpose. It is a more particular object of the invention to provide an improved folding board of this general type which may be used to so fold the uppermost fold of a stack of interfolded webs partially over and across itself and may alternately, with another mode of threading, be effective to provide a flat upper fold so that the board may function in the manner of the fold ing boards in the Greiner and Rutkus Patent 3,066,932, for underfolding a web fold beneath a second fold of a web folded by the board and at the same time interfolding the web with a stack of previously interfolded webs.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects, and such other objects, as will be apparent from the following description of a preferred form of the invention, illustrated with reference to the accompanying drawings, wherein:

FIG. 1 is a front prospective view of a folding board embodying the principles of the invention and having a web passing over the board and being folded by the baord;

FIG. 2 is a view similar to FIG. 1 with the web being threaded differently through the board and thus being folded differently by the board;

FIG. 3 is a sectional view through a stack of interfolded paper webs with the uppermost web being that folded by the board in its operating condition shown in FIG. 1;

FIG. 4 is a view similar to FIG. 3 with the uppermost web being that folded by the folding board in its FIG. 2 operating condition;

FIG. 5 is a top plan view of the folding board;

FIG. 6 is a side elevational view of the folding board;

FIG. 7 is a plan view of the sheet metal blank of which the board is made, prior to bending the blank to form the board;

FIG. 8 is a side elevational view of the board installed in operating position on a platform;

FIG. 9 is a diagrammatic illustration of the folding board setting forth various dimensions and angles of the board;

FIG. 10 is a view similar to FIG. 1 but illustrating a board of opposite hand; and

FIG. 11 is a view similar to FIG. 2 but showing a board of opposite hand.

Like characters of reference designate like parts in the several views.

Referring now to FIGS. 1, 2 and 5 to 8 in particular, the firs-t type of folding device or board illustrated in the drawings, which may be called a lefthand board for the sake of simplifying the terminology, may be seen to comprise fiat sheet metal portions 20, 21 and 22 made from a single piece of sheet metal bent along lines 23 and 24. The portion 22 may be considered as a base portion usually used in horizontal position, and the line 24 on one edge of the base portion, as will hereafter appear, extends parallel with the path of movement A of a web or stack of webs passing over or beneath the folding board and is substantially coincident with one edge of the web stack. The portion 22 terminates in an edge 25 which extends obliquely across the path A. The fiat portion 20 terminates in a lower bend line 26 which also forms one edge of a lip 27, and the line 26 and lip 27 are both in the same plane as the sheet metal portion 22. The bend lines 23, 24 and 26 and also the edge 22 meet at an apex point 28. The line 26 is at right angles with respect to the line 24 and extends transversely and directly across the path of movement A. The line 23 lies in the same plane as the portion 21 and in the same plane as the portion 20 and extends at an obtuse angle with respect to the line 26, as well as extending at angles with respect to the edge 25 and the line 24.

The flat portion 22 is preferably provided with a side extension 22a at one end of the board by means of which the flat portion 22 may be supported from a table 29, for example (see FIG. 8); and the flat portion 20 is provided with an extension 20a by means of which the other end of the board may be supported with respect to the table. An upstanding stud 30 may be fixed with respect to the table 29, and nuts 31 on the stud 30 may be provided both above and below the portion 22a so as to support one end of the board. A standard 32 is illustrated as being fixed on the table 29, and the portion 20a is fixed to a collar 33 that is in turn fixed on the standard 32 for sup porting the other end of the board. The flat portion 22 is preferably disposed horizontally, assuming that the table 29 is horizontal, and is spaced upwardly from the table.

The folding device as so far described is substantially like those described in the above mentioned Greiner and Rutkus Patent 3,066,932; and, as will hereinafter be more fully described, it may function with respect to a web passing over it to underfold one fold of the web with respect to another fold of the web, and in so underfolding, the folding board may interfold the fold being underfolded with the uppermost fold of a stack of previously interfolded webs.

The folding board of the invention also is so designated that it may overfold a Web fold for a portion of. the width of the stack of interfolded Webs; and, for this purpose, the folding board is provided with a folding bar 36 which is welded at 37 to the upper surface of the lip 27 and is provided with a slot 38 in the flat portion 20.

As mentioned, the folding board exclusive of the bar 36 and slot 38 is described in the aforementioned Greiner and Rutkus patent, and the angles to which the various parts should be placed with respect to each other and the relative dimensions of the parts, so that all parts of a web being folded have the same travel as other parts in order to overcome wrinkling, are set forth in the Greiner and Rutkus patent, and this patent may be referred to for these angles and dimensions. In order that a web, which passes through the slot 38 and across the bar 36 in a manner to be hereinafter described, shall also have all of its parts travel substantially the same distance to minimize wrinkling, the slot 38 and bar 36 shall preferably be set at particular angles. The slot 38 and bar 36 are quite similar in principle to the overfolding device illustrated and described in the Greiner-VanIten Patent No. 3,291,479, issued Dec. 13, 1966 (see, for example, FIGS. and of Patent No. 3,291,479), and substantially the same mathematical relationships for locating the slot 38 and bar 36 may be used as for the corresponding parts in the folding device disclosed in Patent No. 3,291,- 479. The angles L, M and N, shown in FIG. 9 herein, may, in particular, be based on the quantities W, e, f and I, similarly to corresponding angles for the folding device of the Greiner-Vanlten Patent No. 3,291,479.

Referring to FIG. 9, the angle M denotes the angle with which the slot 38 is disposed with respect to a vertical line 39 that extends upwardly on the fiat portion from a point 40 which is the substantial point of intersection of the slot 38 and the inner or folding edge 36a of the bar 36. Assuming that the portion 22 is horizontal, the line 39 lies in a vertical plane which also includes a line 41 that is a longitudinal center line of a stack of interfolded webs, with the plane being parallel with the direction of movement A of the folded webs. The side edge of the stack of folded webs, as will hereinafter appear, is substantially along the bend line 24, and a line 42 is an imaginary line in the flat portion 20 extending upwardly and in the same vertical plane as the line 24. The lines 39 and 42 are, of course, parallel, and the same is true for the lines 24 and 41. The angle N is the angle between the bar 36 and the line 24 which is parallel with the direction of web travel A. The angle L is the angle at which the portion 20 extends with respect to the portion 22. The quantity W is equal to the width of the web portion which is folded over by the bar 36-the quantity W may, for example, for the case to be hereinafter described, be equal to one-half of the width of the interfolded stack or to one-fourth the width of a web prior to any folding.

The distance 7 is the distance from the bend line 26 to a line 43 which is the distance W in length and which intersects with both the lines 38 and 42 and is parallel to the line 26. The distance 2 is the component of the distance f along the path A, and l is the distance from the bend line 26 to the intersection of the bar 36 and the line 24.

Utilizing the above mentioned quantities, the angles L, M and N may be determined by the equations:

W2 Cos L One- Tan N =1 2e W Tan .M fi

If these equations are utilized, a web passing through the slot 38 and over the bar 36 has a portion of it overfolded on a lower portion of it without any substantial wrinkling, since all of the portions of the web travel through substantially the same distance while the overfolding is being accomplished by the folding device.

The board illustrated in FIGS. 1 to 9 has, for the sake of simplicity, been above termed a lefthand board, since it will underfold a web from right to left, looking downwardly on the portion 20 and in the direction A. A board of the opposite or right hand is illustrated in FIGS. 10 and 11, and this board is simply a mirror image of the board illustrated in FIGS. 1 to 9. The board shown in FIGS. 10 and 11 has fiat portions 20, 21 and 22, bend or fold lines 26', 23', 24' and 25, a slot 38 in the plane portion 20', and a folding bar 36.

In the operation of the left hand type of board, the web B may be underfolded to provide web folds b and b as illustrated in FIG. 1. The web B moves downwardly along the undersurface of the portion 20, and it travels with its longitudinal center line traversing the point 28 at which the lines 26, 23 and 24 and the folding edge 25 meet. Onehalf of the web B travels under the fold line 26 and lip 27 and from thence in the direction A so as to form the web fold b The other half of the web B travels down the undersurface of the flat portion 20, around the bend line 23, onto the undersurface of the flat portion 21, around the bend line 24 and on the undersurface of the flat portion 22, and it turns degrees around the edge 25 so as to form the web fold b in contact with the upper surface of the fiat portion 22. If a stack of previously interfolded webs is drawn in the direction A underneath the flat portion 22, and if the top web fold c of the stack (see FIG. 3) is trained over the upper surface of the portion 22, the fold b in passing around the folding edge 25 is thereby inserted underneath the web fold 0 in being underfolded beneath the web fold b to thereby interfold the web B with the web C and complete the stack of interfolded webs.

A web C is underfolded so as to underfold a web fold c underneath the web fold 0 in substantially the same manner on a right hand board (see FIG. 10) as the web B is folded by the left hand board, except that, since the parts and folding lines are reversed, the web is folded from the left to the right as seen when looking down on the fiat portion 20 and in the direction A.

An interfolded stack of webs, as shown in FIG. 3, may be produced by the boards functioning as illustrated in FIGS. 1 and 10 and substantially in the same manner described in the aforementioned Greiner and Rutkus Patent 3,066,932. It is assumed that, in making the stack of interfolded webs, as shown in FIG. 3, the righthand board illustrated in FIG. 10 precedes the lefthand board as shown in FIG. 1, and that the web fold a, travels on the top surface of the fiat portion 22. A succession of alternate right and lefthand boards, one for each of the webs being added onto the stack, used with the top Web fold of the Web folded by the preceding board passing over the top surface of a flat portion 22 or 22, will produce as high a stack of interfolded webs as desired, depending on the number of successive folding boards being utilized.

If it is desired that the upper Web fold b, be folded back on itself for one-half the width of the interfolded stack of webs so as to produce the web folds b and b as shown in FIG. 4, then the upper web B is made to pass through the slot 38 and around the folding bar 36. An edge quarter of the web B passes down the undersurface of the fiat portion 20 and through the slot 38; and, from thence, it passes around the folding bar 36, as illustrated in FIG. 2, so that this side quarter of the web produces the fold b which is folded over the remainder of the web fold b which is the quarter width fold b It will be understood that the web folds b and 11 without such overfolding is the web fold b illustrated in FIG. 3 and also that the folding device as illustrated in 'FIG. 2 is at the same time effective to underfold the web fold b beneath the top web fold c of the previously interfolded stack of webs. The overfolding of the web fold b over the web fold b produces a folded web edge on the longitudinal center line of the interfolded stack of webs as illustrated in FIG. 4, so that if a segment of this stack is utilized in a carton having a tissue withdrawal window in its top panel, a person may reach his hand downwardly through the opening and easily grasp the top web B at the fold line between the folds b and b lying directly on top and in the middle of the interfolded stack.

The action of the righthand folding board in providing a top quarter fold on a previously interfolded stack of tissues is illustrated in FIG. 11. In this case, the web C has an edge quarter, as illustrated in this figure, folded into a web fold 0 disposed over the fold c It will be understood that the invention is not to be limited to the specific constructions, arrangements and devices shown and described, except only insofar as the claims may be so limited, as it will be understood to those skilled in the art that changes may be made without departing from the principles of the invention.

What is claimed is:

1. A folding device for folding a web of sheet material comprising first, second and third folding edges extending from a first point in a single plane, said first and second folding edges being at right angles with respect to each other and said third folding edge extending between said first and second folding edges, a fourth folding edge extending from said point at angles to said second and third folding edges and at an obtuse angle with respect to said first folding edge whereby a first longitudinal fold of the web may be drawn over said first folding edge and a second fold of said web may be drawn over said other folding 6 edges and thereby folded under said first fold, a fifth fold ing edge disposed in the plane formed by said first and fourth folding edges and extending from a second point on said first folding edge obliquely of said first edge, and a sixth folding edge crossing said third folding edge and extending obliquely of said first folding edge from said second point whereby said first web fold may be directed across said fifth and sixth folding edges so as to have a portion of it overfolded on the remaining portion of it.

2. A folding device as set forth in claim 1, said first, fourth and fifth folding edges being formed by the edges of a flat piece of sheet material.

3. A folding device as set forth in claim 1, said first and fourth folding edges being provided by the edges of a flat sheet material piece over which the Web travels and said fifth folding edge being provided by a slot provided in said flat sheet material piece which diverges with respect to said fourth folding edge from said first folding edge.

4. A folding device as set forth in claim 1, said second and third folding edges being formed by the edges of a flat piece of sheet material and said sixth folding edge constituting a bar which extends over said fiat sheet material piece.

5. A folding device as set forth in claim 1, said first and fourth folding edges being provided by a first fiat sheet material piece, said second and fourth folding edges being provided by a second sheet material piece fixed with respect to said first sheet material piece, and said second and third folding edges being provided by a third flat sheet material piece fixed with respect to said second sheet material piece.

6. A folding device as set forth in claim 5, said fifth folding edge being provided by a slot formed in said first sheet material piece and said sixth folding edge being provided by a bar fixed with respect to said first sheet material piece and overlying said third sheet material piece.

References Cited FOREIGN PATENTS 1,198,140 12/1959 France.

EUGENE R. CAPOZIO, Primary Examiner.

P. V. WILLIAMS, Assistant Examiner. 

